Classifying apparatus, particularly for sorting coins

ABSTRACT

A drum rotatable about a horizontal axis comprises holes in its peripheral wall, the size of the holes depending on the critical diameter according to which the coins or the respective other materials are to be sorted. A conveyor screw disposed inside the drum serves to move the material continuously through the drum thereby causing the individual pieces to contact the peripheral wall having the holes.

United States Patent 1 Jobst Oct. 9, 1973 CLASSIFYING APPARATUS,

PARTICULARLY FOR SORTING COINS [76] inventor: Ludwig Jobst, Hammannstrasse 26, Munich, Germany [22] Filed: July 20, 1971 [21] Appl. No.: 164,297

[30] Foreign Application Priority Data July 29, 1970 Germany P 20 37 709.7

[52] US. Cl 133/3 R [51] Int. Cl. 607d 3/08 [58] Field of Search 133/3 R, 3 B, 3 E, 133/1 R, 1 A, 8 R;221/199, 198, 460

[56] References Cited UNITEDSTATES PATENTS 686,611 11/1901 Hoey"; 133/3 E 757,612 4/1904 Gilfitlan... 133/] R 1,668,626 5/1928 Brandt 133/3 R 2,646,805 7/1953 Anderson 133/3 R FOREIGN PATENTS OR APPLICATIONS 296,432 5/1932 Italy 133/3 R 738,899 10/1955 Great Britain. 133/3 R 65,896 8/1943 Norway 133/3 R 870,820 6/1961 Great Britain 133/3 R Primary Examiner-Robert B. Reeves Assistant Examiner-David A. Scherbel Attorney-Craig, Antonelli & Hill {5 7] ABSTRACT A drum rotatable about a horizontal axis comprises holes in its peripheral wall, the size of the holes depending on the critical diameter according to which thecoins or the respective other materials are to be sorted. A conveyor screw disposed inside the drum serves to move the material continuously through the drum thereby causing the individual pieces to contact the peripheral wall having the holes.

16 Claims, 5 Drawing Figures PATENTED OCT. 9W3

SHEU l U? INVENTOR Lu DWIG- 30 BST ATTORNEYS CLASSIFYING APPARATUS, PARTICULARLY FOR SORTING COINS BACKGROUND OF THE INVENTION Classifiers, particularly coin sorters, exist in many different embodiments and for many different applications. Most of the known coin sorting devices, however, are either part of a large machinery for varifying, sorting and counting coins or are complicated and expensive due to absolute operating reliability being demanded in most cases. There isthus a need of a small size and portable device which should be as simple as possible. In most of the vending machines, slot machines, music boxes or other automatic machines, the various coins of different denominations accepted by the machine fall into a common coin collector. Sorting is thus required before counting the amount of money accepted by the machine. Due to the absence of an appropriate and efficient device, such sorting is still done manually by the person collecting the money from the automatic machines. A considerable amount of time is required for the manual sorting; for example, the sorting of a sum of I dollars consisting of a mixture of coins of only two different denominations such as dimes and nickels will take about half an hour for a skilled person.

It is thus the general object of the invention to provide an apparatus which is as simple, small-size, lightweight and efficient as possible, which can easily be carried in a hand-bag of the person collecting the money, and which allows an easy and fast sorting of a quantity of coins into two or more groups of denominations.

From German Patent specification No. 124,465, a coin sorter is known having a drum rotatable about a horizontal axis and comprising several cylindrical screens each having a peripheral wall provided with perforations corresponding to the critical diameter according to which the coins are sorted,-one end wall of the drum being provided with a feed opening. The known device is disadvantageous in that the drum holds only a limited amount of coins at a time and has thus to be emptied several times if a greater quantity is to be sorted. For emptying the drum, lateral lids must be opened and the drum has to be tilted out of its horizontal position by means of a lever mechanism. Such tilting may also become necessary during sorting in order to prevent individual coins from moving along the inner drum wall on a line on which no perforations are provided.

A further device for sorting coins is known from German utility model (Gebrauchsmuster) specification No. 1,897,662. This device employs a prismatic body having three longitudinal side walls consisting of rectangular hole plates which are disposed at an acute angle with respect to each other, which can be withdrawn for filling in the coins to be sorted, and which can be replaced for changing the size according to which the sorting is carried out. Also this prior art device has the disadvantage of holding only a limited quantity of coins at a time so that the sorting process has to be interrupted several times when sorting greater quantities. Furthermore, the sorting proper is carried out by shaking the device which is not only considerably noisy but also requires a sufficient large collecting vessel to avoid loss of the coins scattered out of the device.

SUMMARY OF THE INVENTION The present invention overcomes the disadvantages of the prior art devices by providing a classifying apparatus comprising a drum the peripheral wall of which is provided with holes corresponding to the critical diameter, one end wall of the drum comprising an inlet opening and the other end wall comprising a discharge opening; a conveyor screw disposed inside the drum and coaxially therewith, the pitch of the drum being greater than the diameter of the largest object to be sorted; and means for rotating the screw about a substantially horizontal axis.

With an apparatus according to the invention, any desired quantity of material fed to the inlet can be sorted or classified continuously by rotating the drum. The screw conveys the material-in the axial direction along the peripheral wall with the holes whereby smaller pieces pass through the holes, while larger pieces are discharged at the outlet end. Using such apparatus for sorting coins, the amount of dollars consisting of dimes and nickels as mentioned in the above example can be sorted within about two to three minutes. The principle on the invention allows a small size and convenient design of the apparatus.

In order to allow sorting into more than two groups of sizes it is advantageous to provide either an exchangable drum or to form the drum with several sections disposed one behind the other in the axial direction of the drum, the sections having holes corresponding to different sizes and the diameters of the holes increasing from section to section in the direction of the discharge end.

If other material consisting of irregularly shaped pieces is to be classified rather than coins, the peripheral wallof the drum is preferably formed by a screen having correspondingly sized openings.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of this invention will be apparent from the following detailed description and the accompanying drawing, in which:

FIG. 1 is a perspective view of a coin sorting apparatus according to the invention placed on a conventional counting panel;

FIG. 2 is an axial section of the apparatus along the line II-II in FIG. 1;

FIG. 3 is a top view of the feed trough in the direction of the arrow III of FIG. 2;

FIG. 4 is a side view of the drum in another embodiment; and

FIG. 5 is a fragmentary section of a further embodiment of the coin sorting apparatus according to the invention in a view similar to FIG. 2.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS As shown in FIGS. I and 2, the coin sorting apparatus comprises a frame 10 having two end walls 12 and 14 and an intermediate wall 16 disposed parallel thereto. The three walls 12, I4 and 16 are interconnected laterally by longitudinal straps 18. Preferably, the walls l2, l4 and 16 are additionally connected by a bottom strap 20 similar to the lateral straps 18. Two feet 22 are fixed to the bottom strap 20. The feet 22 are shaped and spaced such that they fit into holes of a conventional coin counting panel 24 shown in FIG. 1. The counting panel 24 is not part of the invention.

The end wall 12 is provided with a circular bore 26 which occupies essentially the total area of the end wall 12; a similar but smaller bore 28 is provided in the intermediate wall 16 coaxially of the bore 26. A drum 30 extends between the end wall 12 and the intermediate wall 16, the outer peripheral wall of the drum 30 being supported in the bore 26 at a portion close to one of its ends, and in the bore 28 by a tubular extension 32 provided at its other end. The tubular extension 32 forms a feed opening of the drum while the other end of the drum is open over its entire cross-section and forms a discharge opening. The drum 30 is provided at its discharge end with an annular flange 34 on which a crank handle 36 is rotatably mounted. The drum 30 can be inserted into the fram through the bore 26 (i.e. from the right in FIG. 2) to such an extend that the tubular extension 32 enters the bore 28 in the intermediate wall 16 and the annular flange 34 engages the outer side of the end wall 12. Two longitudinal grooves 38 are provided in the outer surface of the peripheral wall of the drum at its discharge end and disposed diametrically opposite to each other with a retaining spring inserted in each of these grooves. When the drum 30 is inserted into the frame 10 the springs 40 are pressed into the grooves 38 when passing through the bore 26. With the drum 30 in the position shown in Figures 1 and 2, shoulders at the ends of the springs 40 lie close to the inner side of the end wall 12 to prevent inadvertent removal of the drum from the frame. The space between the shoulders of the springs 40 and the inner side of the annular flange 34 is slightly greater than the thickness of the end wall 12 so that the drum 30 is easily rotatable. ln order to remove the drum 30 from the frame 10, the two springs 40 can be pressed into the grooves 38 with two fingers of one hand and the drum can then be passed through the bore 26.

A screw conveyor 42 coaxial with the drum axis A is disposed inside the drum 30, the outer end of the screw being fixed to the inner peripheral wall of the drum by bonding or similar means. The pitch h of the screw 42 is slightly greater than the diameter of the largest coin to be sorted. Preferably, the thread direction of the screw 42 is such that when rotating the drum 30 by the crank handle 36 clockwise, the axial conveying direction of the screw 42 is from the inlet to the outlet (i.e. to the right in FIG. 2). The axial length of the drum 30 is such that the screw 42 which is a single thread screw comprises approximately four complete turns. It has been found that a minimum of three turns is sufficient for a complete sorting. The additional fourth turn is a safety measure of particular significance at higher rotating speeds of the drum. The inner axial portion of the screw 42 is removed so that the screw has a coaxial circular channel 44, the diameter of which equals approximately the diameter of the largest coin to be sorted. if the circular channel 44 is omitted, i.e., ifa full screw is used, it has been found that there is a danger, particularly under full charge conditions of the drums, that coins may jam in the innermost portion of the screw and thus block the screw. If on the other hand the circular channel 44 is too larger there is a danger that the coins pass through this channel and skip one or more turns of the screw in the axial direction.

The peripheral wall of the drum 30 is provided with holes 46 the diameter of which is slightly greater than the respective critical diameter, i.e. the diameter of the smallest coin in the quantity to be sorted. The holes 46 are approximately centered between the flanks of the screw 42. The space between the holes 46 is selected with respect to the material of the peripheral wall of the drum so that the webs retained between the holes have sufficient strength.

An open-top lead-in element 48 of a U-shaped crosssection and inclined inwardly and downwardly in the longitudinal direction is mounted between the end wall 14 and the intermediate wall 16. The lower inner edge ofthe lead-in element is at least as high as the outer end of the inner surface of the tubular extension 32 to prevent the coins from getting stuck at the inlet.

A feed trough 50 is placed on top of the frame 10 in an inclined direction and has an opening 52 (see also FIG. 3) at the lower end of its bottom. When the feed trough 50 is placed on top of the apparatus in its operating position the opening 52 is above the lead-in element 48.

The feed trough 50 has a rectangular shape; the inner dimensions of the trough correspond to one of the four longitudinal surfaces of the frame 10. Two inner webs 54 are provided inside the trough 50 which are fixed at 56 to the inner wall of the trough 50 and are formed with a hinge close to the fixing positions. Preferably, the webs 54 are made from plastics and the hinges" are formed by portions of reduced thickness. The webs 54 extend in there operating position from the fixing points 56 diagonally inwardly so that they form a funnel-shape leading to the opening 52 thereby preventing coins from being left in the lower corners of the feed trough 50. In this position, the webs 54 are held by noses 58 integral with the bottom of the trough 50. When the trough 50 is to be removed and placed upside-down on the frame 10 like a cover, the webs 54 can be moved over the noses 58 and folded against the inner walls of the trough by applying slight pressure so that essentially the full inner cross-section of the trough is available.

A traverse plate 60 is hinged to the lower side of the bottom in a similar way as the webs 54 and is provided with slots 62 by which the traverse plate 60 can be mounted on the upper longitudinal straps 18 of the frame 10. A projection 64 is formed at the lower traverse edge of the feed trough 50 which projection bears in the operating position of the feed trough 50 against the upper inner edge of the end wall 14 inside the leadin element 48. Stops 66 provided at the upper longitudinal straps l8 prevent the traverse plate 60 from folding in the forward direction. The hinge-like mounting of the traverse plate 60 at the bottom of the feed trough 50 allows the apparatus to become as small and compact as possible in its collapsed condition, i.e. when the feed trough 50 is placed as a cover on top of the apparatus.

In operation of the apparatus in its position shown in FIGS. 1 and 2, the quantity of coins to be sorted is charged in the feed trough 50 from where the coins fall through the opening 52 into the U-shaped lead-in element 48 and move to the inlet end of the screw 42. The drum 30 is rotated clockwise by means of the crank handle 56 thereby conveying the coins through the screw towards the outlet end of the drum. This screw motion causes all coins to contact the peripheral wall of the drum while being conveyed, whereby the smallest coins fall through the holes 46. When the apparatus according to the invention is used with the counting panel shown in FIG. 1 those smallest coins passing through the peripheral wall of the drum are brought on such panel in preparation for a subsequent counting process. The remaining coins having a diameter greater than the diameter of the holes 46 are discharged at the outlet end of the drum 30 and fall into a collecting tray 68 which may have been placed there.

The apparatus of FIGS. 1 and 2 thus allows a sorting according to one critical diameter. If the quantity to be sorted contains only coins of two different sizes, the sorting process is thus completed. If on the other hand the original quantity contains three or more different sizes of coins the drum 30 may now be removed from the frame in the above described manner and replaced by another drum having holes with a diameter corresponding to the respective larger coins.

in an alternative embodiment, a drum 30! is used which has a greater axial length and is divided into several portions 30A, 30B and 30'C. The holes in each section are of the same diameter while the diameter increases from section to section in the conveying direction of the screw. in accordance with FIG. 4 the holes 46'A are thus smaller than the holes 46B, and the latter are smaller than the holes 46'C. For the above reasons, each of the sections 30'A, 30'B and 30C is sufficiently long so that the inner screw passing through the drum completes approximately four turns within each section. Obviously, a corresponding number of collecting trays has to be disposed below the various sections of such multiple drum 30. In this case, a multiple sorting according to a plurality of coin sizes is thus carried out in one step.

According to FIG. 5, a small electrical motor 70 may be provided rather than the manually operable crank handle 36, the motor 70 being conveniently mounted on the inner side of the end wall 14 with its driving shaft 72 passing through the intermediate wall 16. A friction roller 74 made from rubber is fixed to the driving shaft 74 and engages the outer side of the peripheral wall of the drum. With this embodiment of the motor drive, an exchange of the drum 30 can easily be done as above.

Essentially all parts of the apparatus are made from plastics. Preferably, the drum 30 consists of transparent material so that the proper conveying of the coins through the screw can easily be supervised.

A coin sorting apparatus has been described as a preferred embodiment of the invention. it should be understood, however, that the principles of the invention can be employed for many other types of classifying apparatuses. Specifically, a classifier for gravel or similar construction material could be designed in accordance with the invention. In this case, the peripheral wall of the drum could be formed by a screen having correspondingly sized sieve openings.

1 claim:

1. A classifying apparatus comprising a drum having a peripheral wall provided with apertures corresponding substantially to the size of objects to be classified,

one end wall comprising an inlet opening and an opposite end wall comprising a discharge opening; a conveyor screw disposed coaxially on the inside surface of the drum, adjacent turns of the screw having a spacing substantially the same size as the largest object to be classified; a central coaxial circular channel formed in said drum by edges of the screw, said channel having a diameter substantially the same size as the largest object to be classified; and means for rotating the drum about a substantially horizontal axis, wherein the diameter of the central channel enables objects to be classifled to be conveyed by the conveyor screw without jamming within the drum and enables such objects to be conveyed without skipping one or more turns of the screw.

2. The apparatus of claim 1, wherein the apertures are substantially centered on the peripheral wall between adjacent turns of the screw.

3. The apparatus of claim 2, wherein the conveyor screw is a single thread screw with at least three turns.

4. The apparatus of claim 1, comprising a frame having two parallel vertical wall means for supporting the drum close to its ends, the drum being insertable into the frame in the direction of the inlet end and being secured within the frame by retaining springs against axial displacement.

5. The apparatus of claim 4, wherein drums having different size apertures are insertable in the frame.

6. The apparatus of claim 4, comprising a feed trough, means for mounting the feed trough on top of the frame in an inclined manner, the trough having at its lower end an opening communicating with the inlet opening of the drum.

7. The apparatus of claim 6, wherein the feed trough can be removed and placed upside down on top of the frame like a cover.

8. The apparatus of claim 7, wherein the trough comprises inner webs movable between a first position in which they form a funnel-shape around the opening, and a second position in which they extend along the inner wall of the trough.

9. The apparatus of claim 4, wherein the frame comprises at least two feet for inserting into a counting panel. 7

10. The apparatus of claim 1, wherein the drum comprises a plurality of sections arranged one behind the other in the axial direction, each section having apertures corresponding to one size of objects to be classifed, the sizes of the apertures increasing from section to section in the direction of the discharge end.

11. The apparatus according to claim 1, wherein said means for rotating includes a crank handle attached to' the discharge end of the drum.

12. The apparatus according to claim 1, wherein said means for rotating includes an electrical motor for driving the drum.

13. The apparatus of claim 1, wherein the conveyor screw and preferably other parts of the apparatus are made from plastics material.

14. The apparatus of claim 1, wherein the drum is made of transparent material.

15. The apparatus of claim 1, wherein the conveyor screw is a single thread screw with four turns.

16. The apparatus of claim I, wherein said conveyor screw conveys objects to be classified along the peripheral wall whereby objects having a size not larger than the size of the apertures pass through the apertures and objects having a size larger than the aperture size are conveyed through the discharge opening. 

2. The apparatus of claim 1, wherein the apertures are substantially centered on the peripheral wall between adjacent turns of the screw.
 3. The apparatus of claim 2, wherein the conveyor screw is a single thread screw with at least three turns.
 4. The apparatus of claim 1, comprising a frame having two parallel vertical wall means for supporting the drum close to its ends, the drum being insertable into the frame in the direction of the inlet end and being secured within the frame by retaining springs against axial displacement.
 5. The apparatus of claim 4, wherein drums having different size apertures are insertable in the frame.
 6. The apparatus of claim 4, comprising a feed trough, means for mounting the feed trough on top of the frame in an inclined manner, the trough having at its lower end an opening communicating with the inlet opening of the drum.
 7. The apparatus of claim 6, wherein the feed trough can be removed and placed upside down on top of the frame like a cover.
 8. The apparatus of claim 7, wherein the trough comprises inner webs movable between a first position in which they form a funnel-shape around the opening, and a second position in which they extend along the inner wall of the trough.
 9. The apparatus of claim 4, wherein the frame comprises at least two feet for inserting into a counting panel.
 10. The apparatus of claim 1, wherein the drum comprises a plurality of sections arranged one behind the other in the axial direction, each section having apertures corresponding to one size of objects to be classified, the sizes of the apertures increasing from section to section in the direction of the discharge end.
 11. The apparatus according to claim 1, wherein said means for rotating includes a crank handle attached to the discharge end of the drum.
 12. The apparatus according to claim 1, wherein said means for rotating includes an electrical motor for driving the drum.
 13. The apparatus of claim 1, wherein the conveyor screw and preferably other parts of the apparatus are made from plastics material.
 14. The apparatus of claim 1, wherein the drum is made of transparent material.
 15. The apparatus of claim 1, wherein the conveyor screw is a single thread screw with four turns.
 16. The apparatus of claim 1, wherein said conveyor screw conveys objects to be classified along the peripheral wall whereby objects having a size not larger than the size of the apertures pass through the apertures and objects having a size larger than the aperture size are conveyed through the discharge opening. 